This application claims the priority of German Patent Application No. 101 11 930.5 filed Mar. 12, 2001, which is incorporated herein by reference.
The invention relates to a system component, particularly for knitting machines or similar textile machines.
The term system component encompasses all parts of a knitting system, particularly parts of a knitting system of a knitting machine that are seated to move. This term especially refers to components that move in translatory fashion and are directly involved in knitting, or any other loop forming process as well as parts that produce a desired structure, such as cutting needles and the like. The invention can notably be used with knitting-machine needles. Aside from needles, system components include selector parts, coupling elements, sinkers, springs, etc.
For knitting machines, known system components such as needles or other knitting tools are seated to be longitudinally displaced in the needle groove of a needle cylinder or a circular-knitting dial. A so-called drive ring having a cam serves to drive the system components. For purposefully actuating system components such as needles, the components are often provided with or coupled to so-called selector parts, elements, or devices which have a butt that can engage and disengage from the cam. The selector part transmits its longitudinal movement onto the needle or knitting tool.
In the servicing of knitting machines or other stitching machines, the knitting tools, which are present in large numbers, frequently must be removed from their guide channels and reinserted, or replaced with new system components or other knitting tools. If a selector element that is separate from the system component or the needle is associated with the component or needle, and there is no fixed connection between the base body of the system component and the selector element, the task of inserting the system component, with the selector element, into the needle groove requires tremendous dexterity.
It is an object of the invention to improve the handling of such system components.
This object generally is achieved with a system component according to the invention, having a selector element that is connected to the base body of the system component for permitting the back-and-forth movement of the system component. The selector element is also seated to move such that it engages and disengages from a drive device. A fastening element or securing means, secures the selector element to the base body so as to protect it against a lateral misalignment in at least one transverse direction. Thus, the system component and the selector element form a unit that can manageably be inserted into the needle groove or another guide conduit and removed from it. This ensures that the base body and the selector element do not come apart during assembly, i.e., the insertion of the system component into the needle groove or other conduit.
The selector device or part is, for example, a separate selector element that is seated on the base body so as to pivot about a pivot axis. The pivot axis extends perpendicular to the flat sides of the base body (needle body), and is therefore oriented transversely to the direction of needle movement. If the system component is a needle, the selector element is disposed, for example, on the side facing away from the needle back, and is seated to pivot toward and away from the needle back. The selector element can be seated with a suitable hinge element, whose bearing surfaces virtually occupy the entire width of the needle body, measured from flat side to flat side of the needle body. This ensures a precise, durable seating of the selector element on the needle body.
The selector element is preferably resiliently prestressed in a pivot direction. A spring element, for example in the form of a leaf spring inserted into the base body or the selector element, can serve this purpose. It is also preferable to produce the leaf spring and the selector element, or the base body, in an integral manner, i.e., in one piece. The entire length of a spring element of this type preferably has essentially the same thickness as the rest of the base body and the rest of the selector element (measured from flat side to flat side).
Also conceivable are embodiments in which the spring element is tapered from its point of connection to the needle body or the selector element toward its end.
The spring element can serve in resiliently prestressing the selector element against a stop. This arrangement simultaneously effects the prestressing of the securing element.
The selector element can be embodied as an elongated selector element that is seated to move in a recess of the base body. Its thickness preferably matches the thickness of the base body (needle body). In the assembled state, the flanks of the needle or guide groove guide the selector element, so it is impossible to separate the selector element and the base body without affecting the fastening element as well. When the needle (system component) is being handled outside of the needle groove (guide conduit), however, the fastening element holds the needle body (base body) and selector device together.
The securing element or means is preferably embodied in the form of the pairing of a protrusion and a recess, which are engaged in the inoperative position of the selector element. The inoperative position is the position assumed by the selector element when it is not subjected to any external forces. For example, the spring element prestresses the selector element against stops or protrusions. At least in this state, the at least one protrusion and aforementioned at least one recess effect a form-fitting connection between the selector element and the base body (needle body) for preventing the selector element from slipping laterally off of the needle body.
In a preferred embodiment, the spring element effects a lateral guidance. One end of the spring element is connected to either the selector element or the base body (needle body). Its other end rests resiliently against the selector element or the base body (needle body). In the region of the resilient contact, a form fit can be effected by a groove-like recess in the surface opposite the end of the spring. The end of the spring is tapered, so it extends into this groove in the countersurface and provides lateral guidance due to the prestressing and the contact of the spring with the side walls of the groove. In another possible embodiment, the end of the spring would not be tapered, but the spring would have a protrusion that would extend into this groove A converse embodiment is also possible: A groove would be embodied in the spring, while the countersurface would have a protrusion that would extend into this groove.
It is also advantageous for the ends of the elongated selector element to rest, at least on one side, against the base body (needle body) relative to the transverse direction defined by the hinge axis.
Advantageous details of embodiments of the invention ensue from the drawing, the description and the dependent claims. The drawing illustrates exemplary embodiments of the invention. Shown are in: